Samaritans

The Samaritans were made up of people brought to Samaria by the Assyrians after conquering the Kingdom of Israel, along with some of the conquered Jews who mixed in with them. They were always ambivalent about the Jews and normative Judaism. In the worst of times, they impeded Jewish life and tried to have the Temple. At other times, they fought side by side with the Jews against their enemies. Their status in Jewish Law was often a point of contention.

Sources

They do not fear Adonoy. A complete fear as is the custom of the [Bnei] Yisroel. And although they converted out of fear of the lions, [nonetheless,] their fear of Adonoy was not a complete fear, (like [Bnei] Yisroel's custom) as it goes on to elaborate, that they were not engaged in Torah [study] and [in performing] the commandments which God commanded the Bnei Yaakov, and they do not practice according to their statutes and according to their law, which they are obligated to practice once they converted, but as the priest who was of the people of Shomron, instructed them…

Rashi on II Kings 17:34:1

When the adversaries of Judah and Benjamin heard that the returned exiles were building a temple to the LORD God of Israel,

Ezra 4:1

“Jacob said to his household, and to all who were with him: Remove the foreign gods that are in your midst, and purify yourselves, and change your garments” (Genesis 35:2).
“Jacob said to his household” – Rabbi Kruspedai said that Rabbi Yoḥanan said: We are not expert in the minutiae of idol worship, like Jacob our patriarch, as we learned: One who finds vessels, and upon them, a figure of the sun, a figure of the moon, or a figure of a dragon, he casts them into the Dead Sea. Rabbi Yoḥanan said: All garments are included in the category of idols…

Bereshit Rabbah 81:3

FOLLOWING closely upon the victory of the Hasmoneans over the Greek armies and their Jewish proteges, there began a dispute over the interpretation of the commandments of the Pentateuch concerning which many of the scholars held varying opinions. These disputes were frequently so serious that they constituted a threat to the existence of the nation. Out of these disputes there emerged three main tendencies which eventually crystallized into three different parties: the Pharisees, the Saducees and the Essenes…

The Jewish Spiritual Heroes, Volume I; The Creators of the Mishna, The Three Main Parties of the Talmudic Period; The Pharisees, The Sadducees, The Essenes